Hydraulic systems are widely used to perform useful work. Common applications are found on earth-moving and mining machines which use hydraulic systems to move various work tools. For example, on a wheeled or track-type loader, the hydraulic system may be used to raise and lower the arms of the loader as well as tilt a bucket or other work tool attached to the end of the movable arms. In such a system, an engine, typically a diesel engine, is mounted on a chassis and connected by way of a drivetrain to a plurality of wheels or continuous tracks to provide locomotion to the machine. The engine also is used to drive one or more hydraulic pumps to maintain pressure within the hydraulic system of the machine. The one or more pumps are in turn connected to one or more valves which then distribute the hydraulic fluid to one or more hydraulic cylinders movably mounted on the machine. The opposite ends of each cylinder are then connected to a movable arm or work tool as indicated above.
While effective, and used pervasively throughout the industrial world, it can be seen that such hydraulic systems are heavily dependent on proper operation of the engine and pumps. With specific reference to the pumps, if any one of the pumps were to fail, the pressure within the system would also fail and the ability of the machine to perform its designated tasks or work function would also fail. In a construction or mining operation this is simply unacceptable. Any amount of downtime, i.e. time during which the machine is not operational, is lost workflow to the owner of the machine, and thus lost profit.
The pump failure can manifest itself in any number of ways including catastrophic or explosive or more prolonged or incremental. With the former, of course this is hazardous to the operator and those around the machine and immediately results in a non-operational machine. As such machines are often operated in very remote locales, the downtime is also often of a significant duration. Not only must parts be brought in to the work site, but a service technician knowledgeable in the repair of the machine must also be brought in to perform the repair. In even worse situations, the machine has to be transported to a repair facility.
The more incremental type of failure can also be extremely costly to the owner of the machine. If the pump were to more slowly deteriorate or fail, parts or particles from the pump can be released into the hydraulic fluid which will then be disseminated through the hydraulic system. This can clog or damage any of the aforementioned components including the valves or hydraulic cylinders as mentioned above, the components of the individual work tools, the hoses, the couplings, or any other component associated with the hydraulic system. These then also need to be replaced or repaired at significant expense and downtime, or at the very least, the entire hydraulic system must be drained to ensure that such particles and particulates do not remain in the system which then results in significant downtime and added labor cost.
Even if a pump failure has not yet taken place, the decreased efficiency with which the pump is operating also results in less output flow and lower profits. If the pump is not performing as it had been designed, the power of the system is necessarily decreased, the engine is required to work harder for less return, fuel consumption increases, maintenance costs increase, and overall productivity decreases.
In light of the foregoing, it can be seen that a need exists for a system and method by which failure of a pump can be predicted ahead of time so as to avoid outright failure and the associated downside indicated above.